Which best describes oogenesis?
a. oogenesis involves mitosis but not meiosis.
b. oogenesis differentiates oogonia directly into eggs.
c. oogenesis starts in development and then is halted until puberty.
d. oogenesis happens in the testes.

Ans. (C). Oogenesis starts in development and then is halted until puberty.

Oogenesis can be defined as a process of differentiation of egg cell (ovum), into a mature ovum that further develops after fertilization. In humans, oogenesis begins in the early stage of embryonic development, during whcih primary oocyte performs meiosis I and forms secondary oocyte. Meiosis in secondary oocyte gets arrested at metaphase II until puberty.

Thus, the correct answer is option (C).

d. organisms have cells with different shapes and functions.

bacterium is not correct